gaskets, no - it's tight enough and i snug it a bit more so the rubber seals good enuff as far as i am concerned.
oil, no - now that there is no "suction" from it being attached to the air cleaner, you should never see any oil there.
just drill and tap a hole in the center of the plate for the stud. use a nut to keep it tight and also loc-tite or super glue to hold it in good... then grind/sand down the back so it is smooth.
good luck! my next mod will be to add a heavy clear plastic cover with LED's inside
